Here we have four high-resolution image maps of the 4 levels in Sky Skipper. Click the thumbnail for the full-size version.

What I find to be interesting is the detail on some sprites and the sheer ‘blockiness’ on others. It’s easy to see that even if the game was considered ‘finished’ from a code development standpoint, it didn’t have the same amount of quality-control and attention to detail put into the sprites as did the other Nintendo arcade releases.